Ingredients
Scale
- 3 tablespoons unsalted butter
- 2 pounds yellow or sweet onions, thinly sliced
- 4 cloves garlic, smashed
- 1 tablespoon balsamic glaze
- 1 teaspoon herbes de provence
- ½ teaspoon salt, or to taste
- ¼ teaspoon black pepper
- 3 cups beef bone broth
- 3 cups chicken bone broth
- parmesan cheese crisps for topping
Instructions
- Combine sliced onions, butter, balsamic glaze, herbes de provence, salt, and pepper in the slow cooker and stir to coat the onions.
- Cover and cook on high for 6-7 hours or low for 10-12 hours, stirring occasionally until the onions are golden and caramelized.
- Add the beef and chicken broth to the slow cooker, stir to combine, and cook for an additional 30-60 minutes on high to meld the flavors.
- Serve topped with parmesan cheese crisps as desired.
Notes
For a richer flavor, consider adding a splash of Worcestershire sauce along with the broths.
Adjust the salt and pepper according to your taste preference.
This soup can be made ahead and tastes even better the next day.
- Prep Time: 15 minutes
- Cook Time: 12 hours
- Category: Soups
- Method: Slow Cooker
- Cuisine: French
Nutrition
- Serving Size: 1 bowl
- Calories: 320
- Sugar: 7g
- Sodium: 800mg
- Fat: 14g
- Saturated Fat: 7g
- Unsaturated Fat: 4g
- Trans Fat: 0g
- Carbohydrates: 36g
- Fiber: 3g
- Protein: 15g
- Cholesterol: 30mg